Method of launching a projectile using compressed gas



July 28, 1964 J. R. R. HARTER METHOD OF LAUNCHING A PROJECTILE USING COMPRESSED GAS Filed May 22, 1958 2 Sheets-Sheet l INVENTOR JAMES RR. HARTER ATTORNEY July 28, 1964 J. R. R. HARTER 3,142,293

I METHOD OF LAUNCHING A PROJECTILE USING COMPRESSED GAS Filed May 22, 1958 2 Sheets-Sheet 2 BY%M ATTORNEY United States Patent 3,142,293 METHOD OF LAUNCHING A PROJECTELE USING COMPRESSED GAS James R. R. Harter, 4953 Brandywine St. NW., Washington, DE. Filed May 22, 1958, Ser. No. 737,174 2 Gaines. (Cl. 124-11) This invention relates to a device for launching a projectile propelled forwards by the jet action of a compressed gas expanding rearwardly from a container mounted in the projectile. More particularly, the invention deals with a spear fishing gun, sometimes called harpoon gun, operating on this principle.

This application is a continuation-in-part of the application Serial No. 593,309, filed June 13, 1956, now abandoned, which, in turn, is a continuation-in-part of application Serial No. 459,667, filed October 1, 1954 and now abandoned.

It has been suggested to use compressed gas in connection with the propulsion of model airplanes and toy rockets. However, in all such cases, aiming at a particular target is not required. The projectiles are launched by merely piercing a seal provided in the container of compressed gas whereupon the jet action of the escaping gas has to first overcome the inertia of the projectile mass. A comparatively large amount of gas is needed to overcome the mass inertia and to accelerate the mass to maximum speed, and during such time the projectile readily takes any direction which depends on the prevailing conditions beyond control,

The invention, for the first time, provides a device and a method for launching a projectile which follows a directed path towards a chosen target, such as desirable in underwater fishing pistols and spears. This is accomplished by means of a pistol in which a piercing pin is thrusted towards the seal in the outlet orifice of the gas container, which pin after having pierced the seal is caused to continue its movement along a path sufiiciently long to thereby impart a substantial speed to the projectile under its thrusting action. As a result, the inertia of the projectile is overcome by the force imparted exclusively by the pin and the jet action takes over when the projectile is well started. The starting action produced by the piercing pin takes place, when the projectile is still inside of the barrel of the gun, such that the projectile leaves the pistol in the direction of the barrel and with considerable speed which both assure the possibility for aiming with success at a chosen object, e.g. a fish.

The spear fishing guns or harpoon guns, as they are sometimes called, of the prior art, operate on the principal that the gun throws the projectile through the water. By this is meant that the gun provides the propellant and once the spear is launched, away from the gun, the energy of the propellant is removed from the spear. This being the case, it is quite obvious that the maximum speed of the spear is immediately after it has left the gun. It then proceeds to slow down and come to a full stop after expanding all of the energy supplied to it by the propellant. The prior art guns of the thrown type are broadly speaking, divided into two specific classes. The first class is that which provides a propellant in the form of a resiliant member such as a spring; the second class is that which provides a propellant in the form of a pressurized gas such as carbon-dioxide. An example of the former is the patent to Potter, No. 2,404,249. An example of the latter is the patent to Blakeslee, No. 2,660,993.

One of the main disadvantages in the pistols or guns of the thrown type is that it is extremely difficult to supply to the spear, suificient energy to make it travel at any very high speeds underwater or for any great distance. For instance, where the propellant is a spring, due to 3,142,293 Patented July 28, 1954 practical consideration, the spring has to be somewhat limited in size. On the other hand, where the propellant is a gaseous propellant, the gas only works on the spear during the time that the spear is confined in the barrel of the gun. In addition to this disadvantage of the prior art devices, they also are usually very large and bulky. It is diificult to aim them under water and in most cases, extremely difficult to load them. The present invention overcomes all of the deficiencies of the prior art weapons by providing a very light and compact pistol which can easily be aimed and fired with one hand and which is extremely easy to reload. One of the main features of the present invention is that the projectile is a rocketpropelled projectile. The gun is used to initiate the propuision and to aim the projectile. The projectile, being rocket-propelled, reaches very high speed, and is extremely accurate. Its maximum velocity is maintained for considerable length of time and its trajectory is extremely straight and accurate due to the sustained thrust in flight.

Therefore, it is an object of this invention to provide a spear-fishing pistol primarily for underwater use which employs a rocket-propelled projectile and which is extremely accurate and easy to handle.

This and other objects will be apparent from the following description of the accompanying drawings.

FIGURE 1 is a side elevation of one embodiment of the present invention, having parts of the gun broken away,

FIGURE 2 is a view taken along the line 2-2 of FIG- URE 1,

FIGURE 3 is a top plan view of FIGURE 1, except that in FIGURE 3, the gun is in a cocked position whereas in FIGURE 1, it is in the uncooked position,

FIGURE 4 is a side-view of the embodiment of FIG- URES 1 to 3, the pistol being in the cooked position and being partly broken away,

FIGURE 5 is another embodiment of the invention, showing a side-view thereof but with parts broken away, and

FIGURE 6 is a view taken along the lines 66 of FIGURE 5.

First turning to the first embodiment illustrated in FIG- URES 1 to 4 inclusive, the projectile indicated broadly by the numeral 14 is comprised of a shaft 11, over one end of which is detachably mounted the spearhead 12. This spearhead 12 merely fits over the shaft 11 and if for instace a fish is hit, the fish maneuvers the head 12 off of the shaft 11 and, consequently, has much less leverage with which to work the spear loose from himself. The spearhead also has mounted thereto in the usual fashion, folding flukes 13. The line 14 is held in any convenient manner in the line receptacle 15 and extends through loose rings 16 on the shaft 11 of the projectile 10 and finally is attached to the detachable head 12. It is quite apparent then that both the spear itself and its detachable head can be retrieved.

To the other end of the shaft 11 is mounted by any convenient means such as by screw-threads, a housing 17. This housing 17 forms a chamber into which is inserted a gas cylinder 18. This cylinder may be the ordi- I nary CO cylinder. The cylinder 18 is held in place by virtue of a sleeve 19, which is screw-threaded to the housing 17, and has an inwardly extended annular shoulder 20 which prevents the cylinder 18 from falling out of the housing. This sleeve 19 is also provided with a plurality of vanes 21 which guide the projectile during its flight. The gas cylinder 18 has a frangible portion 22 best seen in FIGURE 2 which is pierced by the firing pin 23. To align the projectile 10 so that the firing pin 23 can pierce the frangible portion 22 of the cylinder 18, said projectile is mounted to the barrel 24 of the pistol. In FIGURE 1, the projectile 10 is mounted in the barrel when the pistol is in the uncocked position. Being in this position, the firing pin 23 extends quite a way down the barrel 24 and consequently the projectile cannot be fully engaged in the barrel 24 because of the gas cylinder 18. However, as shown in FIGURE 3, which shows the pistol in a cocked position, the barrel 24 has a plurality of slots which are aligned with the vanes 21 so that the rojectile can be frictionally engaged in the barrel 24, and held in this position until urged out by the firing of the pistol. FIGURE 4 shows a means for assisting in retaining the projectile in the barrel. A spring member 25a is mounted in a bracket 57. This spring is shaped to engage the lowermost projection of a vane when the projectile is in position for firing. The forward extension of the spring 25:: holds the line 14 against the line-holder 15 to prevent escape of the line prematurely until the projectile leaves the barrel.

Turning to FIGURE 4, the pistol is shown in the cocked position, with the projectile 10 in loaded position in the barrel 24. The firing pin 23 is in its fully withdrawn position. It can be seen that at the extreme right-hand end of the firing pin 23 is mounted an enlarged portion of the firing pin indicated as 26. This may be integral with the portion of smaller diameter 23 or may be mounted thereto in some convenient fashion. In any event there is provided by this arrangement between portions 23 and 26 a shoulder 27. The trigger and safety lock members engage against this shoulder and the pistol cannot be fired until these members are withdrawn. As can be seen, the firing pin 23 has a head portion 28 provided with a groove 29 on the periphery thereof which groove receives an elastic member 30. This elastic member is mounted at its ends to ears 31. This particular arrangement is best shown in FIGURE 3. In the cocked position, the elastic member 30, which can be a rubber band, urges the firing pin towards the left as shown in FIGURE 4 and consequently urges the firing pin towards engagement with the frangible portion 22 of the gas cylinder 18. However, the trigger 32 which carries the ears 31 has a latch portion 33 which is normally urged into the opening 34 in the breech 35. It can be seen that the trigger 32 is pivotally mounted to pin 36 and that by virtue of the ears 31 and the rubber band 30, the trigger 32 is normally urged to pivot about the pin 36 in a clockwise direction. Consequently, the latch member 33 of the pin 32 is normally urged into the opening 34 of the breech 35. When the firing pin is withdrawn into the cocked position, and the shoulder 27 of the firing pin is aligned in the opening 34 of the breech 35, the latch 33 engages against said shoulder and prevents the firing pin from moving to the left under the unfiuence of the rubber band 39. Of course, now if the finger portion 37 of the trigger 32 were operated by pulling it in a counter-clockwise direction, the latch 33 would move away from the shoulder 27 and the firing pin would be thrown against the frangible portion 22. However, there is a safety mechanism which is provided to prevent accidental firing of the pistol.

The safety mechanism consists of a second latch member 38. This latch member 38 is also normaly urged into an opening 39 in the breech 35. The latch member 38 is an extension of the grip safety member 40 which is also pivotally mounted to the pin 36. It is normally urged in a counter-clockwise direction by the spring member 41. The spring member 41 engages the grip safety 40 in a pair of notches 42 which are provided for this purpose. The other end of the spring 41 bears against a cam 43. This cam is mounted for pivotal movement around a pin 44. The pin 44 in turn is monuted to a U-shaped bracket 45. This bracket 45 is mounted by virtue of a pin 46 to a pair of braces 47. There is one of these braces mounted on each side of the breech 35, as for instance, shown in FIGURE 3. At the bottom of these braces, there is a spanning member 48 carrying at least one pin 49 to anchor the two braces 47 together.

It can be seen that the spring 41 normally urges the cam to rotate in a clockwise direction and when the finger portion 37 of the trigger 32 is in its furthermost clockwise direction, that is, having the latch 33 engaging the shoulder 27, the cam 43 rotates until it bears against the shoulder 50 of the grip-safety member 49. This places the portion 51 of the cam against the underside of the finger portion 37 of the trigger 32.

In order to fire the pistol, it can be seen that the latch members 33 and 33 must be withdrawn from their contact with the shoulder 27 of the firing pin 23. The latch member 33 cannot be removed until the latch member 38 has been removed. Therefore the pistol cannot be fired accidentally. In order to actuate the trigger, the latch member 38 must first be withdrawn from contact with the shoulder 27. This is done by pressing the palm of the hand while gripping the pistol in the normal fashion, against the grip safety member 40. This rotates this member 40 about the pin 36 in a clockwise direction to thereby withdraw the latch member 38. In doing so, the shoulder 50 of the grip safety 40 moves against the cam 43 to rotate it in a counter-clockwise direction against the spring 4E. The portion 51 of the cam 43 is then moved out of the contact with the underside of the finger portion 37 of the trigger 32. In this position, the trigger then is free to be operated. By pulling the finger portion 7 of the trigger 32 in the counter clockwise direction, and thereby rotating the trigger about the pin 36, the latch 33 comes out of the opening 34 in the breech 35 and consequently comes out of engagement with the shoulder 27, thus clearing the firing pin for operation under the influence of the rubber band 30. When this occurs the firing pin travels at great speed down through the bore of the breech 35 until the firing pin point 53 pierces the frangible portion 22 of the gas cylinder 18 and at the same time starts launching the rocket, freeing it from the spring retaining element 25a. The relationship between the distance is shown in FIGURE 4. The first portion of the path of the firing pin point 53 is the distance A, measured from the firing pin point 53 in the cocked position to the frangible seal 22 in the cylinder 18 which seal is located at the left-hand side of the distance A in FIGURE 4, but not visible since hidden inside of the projectile 10 within the barrel 24. The distance A suitably amounts to about half the full length of the stroke represented by the distance B. Therefore, the firing pin point 53, after having arrived at the end of the distance A and thereby having pierced the frangible seal 22, continues its way until reaching the left-hand end of distance B. During this secend portion of its movement, the firing pin imparts an initial speed to the projectile thereby overcoming the mass inertia of the projectile. Additionally, the piercing point 53 stays in contact with the pierced seal, thereby substantially plugging the outlet until the entire distance B is run through. Only then, when the shoulder 27 hits the lefthand end of the bore 52, the firing pin 23 stops moving whereas the projectile continues, whereby the piercing point is removed from the pierced seal 22 which then be comes an outlet for the expanding gas. It will be noted that the very end of the firing pin 23 has an enlarged annular ring mounted thereto indicated at 54 which is merely to prevent accidental withdrawal of the firing pin upon cocking, to such an extent as to completely remove the firing pin 23 from the smaller bore 55. It would then be rather difficult to thread the small portion of the firing pin 23 back into the small bore 55. In addition, there is provided at the extreme left-hand end of the bore 52 some sort of resilient gasket to absorb the shock of the shoulder 27 when it comes to the end of this bore 52. Also there is provided a rubber gasket 56 about the enlarged portion 26 to absorb the shock of the head 28 impinging on the end of the breech 35. Of course, grip handles are provided such as illustrated by numeral 76.

It should be noted that the firing pin physically frees the projectile from the means used to retain said projectile in the barrel. In doing this, the rocket energy is conserved since it is not employed to initially free the rocket from its frictional engagement in the barrel. If this were not so, the rocket energy would have to be expanded for this initial step. This combined piercing-launching action by the firing pin is accountable for approximately 20 percent of the total range of the projectile. Thereafter, and when the projectile moves out of the barrel 24, the jet action takes over. The line 14 easily unwinds out of the line-holder 15 after the firing pin causes initial launching thrust which releases the line from the spring retainers 25a, and the projectile continues on its course until either it strikes an object or the gas within the gas cylinder is completely expanded. At that time, the projectile is retrieved by manually pulling in line 14. As can be seen, the line-holder 15 is mounted by a bracket 57 in some convenient means to the barrel 24 such as by the cylinder 58 which, in turn, is mounted about the outside portion of the barrel 24.

Returning to FIGURE 1 for a moment, after firing, the components of the gun are in the position as shown, with the exception of course that the projectile is no longer present in the barrel. Shown also in this figure is the specific means, namely, screws 59, for mounting the bracket 57 to the cylinder 58.

The second embodiment of the present invention is shown in FIGURES 5 and 6. The only difierence between this embodiment and the one previously described and illustrated with relation to FIGURES 1 and 4, is that the barrel is difierent and, consequently, this makes the projectile somewhat different. It has been noted by the inventor that due to the slots 25 in the barrel 24 of the first embodiment, some of the thrust is lost. T decrease this loss of thrust, a solid barrel has been used. This solid barrel is shown in the second embodiment illustrated in FIGURES and 6, and identified by numeral 60. The projectile 61 is somewhat different in that the housing 62 has no guiding vanes. The housing is in fact divided into two portions, the two portions being connected together by a bayonet-slot connection. The gas cylinder 63 is contained in the housing in the usual fashion and the rear of the housing provides an inwardly extending annular shoulder 64 to keep the gas cylinder in place within the housing. A similar line retaining means is also employed.

Now, this new type of barrel 60 is provided with a means to retain the projectile 61 in place in the barrel until the pistol is fired. This particular means is best shown in FIGURE 6. The housing 62 is provided with an annular depression or groove which when the projectile 61 is in place, is aligned with the spring members 65. The spring members 65 include springs 66 contained within the spoke cylinder 67. These springs normally urge nylon ball-bearings 68 into engagement with the annular groove provided in the housing 62. All of these spring arrangements 65 are mounted to an annular ring 69 and the springs 66 are kept within the cylinder 67, by virtue of the floating caps 70. By virtue of this detent arrangement, the projectile 61 is held in light frictional engagement within the barrel 60 and can easily be forced out of the barrel when the pistol is fired. The firing of the pistol is exactly the same as that previously described with relation to FIGURES 1 to 4 inclusive. The frangible portion of the gas cylinder is broken by the firing pin and the force of the firing pin hitting the gas cylinder is enough to overcome the inertia of the projectile 61 to the extent that it is urged out of engagement with the spring arrangement just described and the outlet provided by the piercing of the frangible portion the gas cylinder permits escape of the compressed gas when the firing pin comes to rest and the projectile continues its way. The retrieving system is identical to that previously described with relation to the first embodiment. There is shown however, in FIGURE 5 a somewhat different detachable head than that shown with relation to the first embodiment. This head is indicated at 71 and has the same type of folding fiukes indicated at 72 as that previously described with relation to the first embodiment. However, the detachable head 71 fits over the shaft 73 in a somewhat different manner in that it is provided with extending lugs 74 which engage into slots provided in the head 71.

A plurality of channels are provided such as indicated at 75 in FIGURE 4 to allow the water in the breech to escape as the firing pin moves down the bore. This is functionally necessary if the firing pin is larger at one end thus causing a piston action which must be pressure relieved. A notched firing pin of constant diameter would not require this provision.

What has been described are two embodiments of the present invention. Other embodiments obvious to those skilled in the art from the teachings herein are contemplated to be within the spirit and scope of the claims herein. The invention does not contemplate any particular materials to be used in the construction of this pistol. It contemplates any desirable materials that may be found useful; such materials as plastic or aluminum or perhaps stainless steel can be used for the main parts of the pistol. It is contemplated to be within the spirit and scope of this invention that the gun can be made either by machining or by molding the various elements which go to make up the entire device.

What is claimed is:

1. A method for launching a projectile, which is propelled forwards under the jet action of compressed gas expanding rearwardly from a container mounted therein, the container having a pierceable seal in an outlet orifice, which method comprises thrusting a piercing member towards the outlet orifice, piercing the seal therein, continuing thrusting the piercing member along a path sufficiently long to thereby impart a substantial speed to the projectile under the thrusting action, simultaneously maintaining the pierced seal plugged by the piercing member during the thrusting action and stopping the movement of the piercing member at the end of the path.

2. A method for launching a projectile, which is propelled forwards under the jet action of compressed gas expanding rearwardly from a container mounted therein, the container having a pierceable seal in an outlet orifice, which method comprises thrusting a piercing member towards the outlet orifice, piercing the seal therein, continuing thrusting the piercing member along a path sufficiently long to thereby impart a substantial speed to the projectile under the thrusting action, simultaneously maintaining the pierced seal in the outlet orifice substantially plugged by the piercing member and stopping the movement of the piercing member at the end of the path to unplug the outlet orifice.

References Cited in the file of this patent UNITED STATES PATENTS 1,693,414 Tolliver Nov. 27, 1928 2,155,913 Thompson et al. Apr. 25, 1939 2,733,699 Krinsky Feb. 7, 1956 2,860,620 Eflinger Nov. 18, 1958 2,957,468 Enfield Oct. 25, 1960 2,964,031 Dotson Dec. 13, 1960 FOREIGN PATENTS 475,845 Italy Nov. 19, 1952 OTHER REFERENCES Popular Science Monthly, July 1945, page 152 cited. 

2. A METHOD FOR LAUNCHING A PROJECTILE, WHICH IS PROPELLED FORWARDS UNDER THE JET ACTION OF COMPRESSED GAS EXPANDING REARWARDLY FROM A CONTAINER MOUNTED THEREIN, THE CONTAINER HAVING A PIERCEABLE SEAL IN AN OUTLET ORIFICE, WHICH METHOD COMPRISES THRUSTING A PIERCING MEMBER TOWARDS THE OUTLET ORIFICE, PIERCING THE SEAL THEREIN, CONTINUING THRUSTING THE PIERCING MEMBER ALONG A PATH SUFFICIENTLY LONG TO THEREBY IMPART A SUBSTANTIAL SPEED TO THE PROJECTILE UNDER THE THRUSTING ACTION, SIMULTANEOUSLY MAINTAINING THE PIERCED SEAL IN THE OUTLET ORIFICE SUBSTANTIALLY PLUGGED BY THE PIERCING MEMBER AND STOPPING THE MOVEMENT OF THE PIERCING MEMBER AT THE END OF THE PATH TO UNPLUG THE OUTLET ORIFICE. 